Nearly every branch of science and technology uses some form of spectroscopy, in which light is dissected into its component wavelengths to determine color very precisely. Spectrometers allow us to tell exactly how much of a given element is on a planet's surface, or how old a bloodstain on a carpet is. But they are often large and bulky, and the better they are, the bulkier. Researchers have found a way to fit a powerful and precise spectrometer into a camera the size of your phone's — heralding a future of hyper-accurate sensors that could improve scientific instruments or keep your home safe.
Normally, spectrometers use a series of carefully tuned lenses to separate and measure the light's wavelengths. Jie Bao and Moungi Bawendi of MIT found a way to make an ordinary off-the-shelf image sensor capable of discerning a variety of wavelengths with very high precision: by coating it with "quantum colloidal dots," nanoscopic bits of material that react to light depending on their size.
A few of one size here, a few of another size there, and suddenly light striking the sensor is automatically sorted into narrow segments of the spectrum. The process is relatively easy and cheap, and the result is vastly smaller than comparable optical instruments. It could be easily integrated into satellites, phones, appliances, cars — anything that uses a camera.
The research, published Wednesday in the journal Nature, is still in its early stages, but is very promising.